A Climate Study of Daily Temperature Change From the Previous Day By Matt Masek 14th High Plains AMS/NWA Conference

Outline Data Monthly Statistics Effects of Precipitation Strong Frontal Passages Extreme Values Final Thoughts

Data North Platte (LBF) Daily Observation 111 Years or 40,542 Days July 1, 1899 (June 30,1899) to June 30, 2010 Day 2 Compared To Day 1 (D2-D1=X) Highs Lows Average Temperature (no rounding) X can be Positive, Negative, or 0 (Equal)

High Temperatures Month Total Days Positive D2-D1 Negative D2-D1 Equal D2-D1 Jan 3,441 1,697 49.3% 1,579 45.9% 165 4.8% Feb 3,135 1,605 51.2% 1,410 45.0% 120 3.8% Mar 1,809 52.6% 1,516 44.1% 116 3.4% Apr 3,330 1,763 52.9% 1,457 43.8% 110 3.3% May 1,840 53.5% 1,446 42.0% 155 4.5% Jun 1,751 1,389 41.7% 190 5.7% Jul 1,768 51.4% 1,475 42.9% 198 5.8% Aug 1,743 50.7% 1,469 42.7% 229 6.7% Sep 1,666 50.0% 1,512 45.4% 152 4.6% Oct 1,728 50.2% 1,587 46.1% 126 3.7% Nov 1,624 48.8% 1,578 47.4% 128 Dec 1,632 1,644 47.8% Yr Total 40,542 20,626 50.9% 18,062 44.6% 1,854

Low Temperatures Month Total Days Positive D2-D1 Negative D2-D1 Equal D2-D1 Jan 3,441 1,523 44.3% 1,708 49.6% 210 6.1% Feb 3,135 1,415 45.1% 1,514 48.3% 206 6.6% Mar 1,568 45.6% 1,667 48.4% 6.0% Apr 3,330 1,522 45.7% 1,623 48.7% 185 5.6% May 1.568 1,674 48.6% 199 5.8% Jun 1,533 46.0% 1,573 47.2% 224 6.7% Jul 1,526 1,600 46.5% 315 9.2% Aug 1,485 43.2% 1,676 280 8.1% Sep 1,395 41.9% 1,733 52.0% 202 Oct 1,447 42.1% 1,772 51.5% 222 6.5% Nov 1,402 1,710 51.4% 218 Dec 1,479 43.0% 1,752 50.9% Yr Total 40,542 17,863 44.1% 20,002 49.3% 2,677

Average Temperatures Month Total Days Positive D2-D1 Negative D2-D1 Equal D2-D1 Jan 3,441 1,776 51.6% 1,582 46.0% 83 2.4% Feb 3,135 1,620 51.7% 1,422 45.4% 93 3.0% Mar 1,844 53.6% 1,517 44.1% 80 2.3% Apr 3,330 1,777 53.4% 1,460 43.8% 2.8% May 1,816 52.6% 1,497 43.5% 128 3.7% Jun 1,774 53.3% 1,434 43.1% 122 Jul 1,719 50.0% 1,568 45.6% 154 4.5% Aug 1,648 47.9% 1,634 47.5% 159 4.6% Sep 1,626 48.8% 1,581 123 Oct 1,685 49.0% 1,656 48.1% 100 2.9% Nov 1,588 47.7% 1,630 48.9% 112 3.4% Dec 1,642 1,687 3.3% Yr Total 40,542 20,515 50.6% 18,668 46.6% 1,359

Precipitation Compare Day 1 Received Rain Compare Day 2 Received Rain Both Day 1 & Day 2 Received Rain Positive Negative Neutral (Equal to 0)

High Temperatures Month Total Days Positive D2-D1 Negative D2-D1 Equal D2-D1 Jan 3,441 1,697 49.3% 1,579 45.9% 165 4.8% Feb 3,135 1,605 51.2% 1,410 45.0% 120 3.8% Mar 1,809 52.6% 1,516 44.1% 116 3.4% Apr 3,330 1,763 52.9% 1,457 43.8% 110 3.3% May 1,840 53.5% 1,446 42.0% 155 4.5% Jun 1,751 1,389 41.7% 190 5.7% Jul 1,768 51.4% 1,475 42.9% 198 5.8% Aug 1,743 50.7% 1,469 42.7% 229 6.7% Sep 1,666 50.0% 1,512 45.4% 152 4.6% Oct 1,728 50.2% 1,587 46.1% 126 3.7% Nov 1,624 48.8% 1,578 47.4% 128 Dec 1,632 1,644 47.8% Yr Total 40,542 20,626 50.9% 18,062 44.6% 1,854

Positive Day 2 High Temp with Precip Month Total Days Positive Day 1 Rain Positive Day 2 Rain Positive Both Rain Jan 1,697 567 33.4% 375 22.1% 228 13.4% Feb 1,605 617 38.4% 360 22.4% 237 14.8% Mar 1,809 737 40.7% 441 24.4% 285 15.8% Apr 1,763 736 41.7% 511 29.0% 302 17.1% May 1,840 891 48.4% 730 39.7% 451 24.5% Jun 1,751 846 48.3% 708 40.4% 439 25.1% Jul 1,768 769 43.5% 644 36.4% 353 20.0% Aug 1,743 688 39.5% 570 32.7% 303 17.4% Sep 1,666 575 34.5% 381 22.9% 211 12.7% Oct 1,728 489 28.3% 260 15.0% 163 9.4% Nov 1,624 473 29.1% 263 16.2% 158 9.7% Dec 1,632 503 30.8% 296 18.1% 186 11.4% Yr Total 20,626 7,891 38.3% 5,539 26.9% 3,316 16.1%

Negative Day 2 High Temp with Precip Month Total Days Negative Day 1 Rain Negative Day 2 Rain Negative Both Rain Jan 1,579 549 34.8% 747 47.3% 385 24.4% Feb 1,410 529 37.5% 795 56.4% 404 28.7% Mar 1,516 607 40.0% 914 60.3% 475 31.3% Apr 1,457 642 44.1% 887 60.9% 494 33.9% May 1,446 767 53.0% 925 64.0% 559 38.7% Jun 1,389 724 52.1% 830 59.8% 500 36.0% Jul 1,475 691 46.8% 829 56.2% 457 31.0% Aug 1,469 660 44.9% 768 52.3% 422 Sep 1,512 538 35.6% 729 48.2% 374 24.7% Oct 1,587 410 25.8% 630 39.7% 264 16.6% Nov 1,578 453 671 42.5% 313 19.8% Dec 1,644 531 32.3% 749 45.6% 356 21.7% Yr Total 18,062 7,101 39.3% 9,474 52.5% 5,003 27.7%

Equal Day 2 High Temp with Precip Month Total Days Equal Day 1 Rain Equal Day 2 Rain Equal Both Rain Jan 165 58 35.2% 54 32.7% 32 19.4% Feb 120 50 41.7% 47 39.2% 34 28.3% Mar 116 53 45.7% 43 37.1% 28 24.1% Apr 110 55 50.0% 45 40.9% 25.5% May 155 69 44.5% 86 55.5% 46 29.7% Jun 190 97 51.1% 103 54.2% 62 32.6% Jul 198 85 42.9% 82 41.4% 38 19.2% Aug 229 93 40.6% 90 39.3% 24.0% Sep 152 35 23.0% 40 26.3% 16 10.5% Oct 126 27.0% 22.2% 18 14.3% Nov 128 33 25.8% 21.9% 12.5% Dec 52 31.5% 28.5% 24 14.5% Yr Total 1,854 714 38.5% 693 37.4% 397 21.4%

Positive Day 2 Low Temp with Precip Month Total Days Positive Day 1 Rain Positive Day 2 Rain Positive Both Rain Jan 1,523 306 20.1% 434 28.5% 174 11.4% Feb 1,415 323 22.8% 445 31.4% 187 13.2% Mar 1,568 371 23.7% 578 36.9% 229 14.6% Apr 1,522 392 25.8% 631 41.5% 259 17.0% May 562 35.8% 815 52.0% 25.0% Jun 1,533 596 38.9% 744 48.5% 387 25.2% Jul 1,526 535 35.1% 680 44.6% 320 21.0% Aug 1,485 476 32.1% 627 42.2% 291 19.6% Sep 1,395 274 444 31.8% 170 12.2% Oct 1,447 184 12.7% 376 26.0% 122 8.4% Nov 1,402 227 16.2% 384 27.4% 140 10.0% Dec 1,479 284 19.2% 431 29.1% 171 11.6% Yr Total 17,863 4,530 25.4% 6,589 2,842 15.9%

Negative Day 2 Low Temp with Precip Month Total Days Negative Day 1 Rain Negative Day 2 Rain Negative Both Rain Jan 1,708 799 46.8% 666 39.0% 429 25.1% Feb 1,514 794 52.4% 682 45.0% 443 29.3% Mar 1,667 933 56.0% 723 43.4% 500 30.0% Apr 1,623 937 57.7% 720 44.4% 499 30.7% May 1,674 1,061 63.4% 803 48.0% 584 34.9% Jun 1,573 945 60.1% 770 49.0% 530 33.7% Jul 1,600 848 53.0% 716 44.8% 26.8% Aug 1,676 840 50.1% 679 40.5% 417 24.9% Sep 1,733 796 45.9% 630 36.4% 387 22.3% Oct 1,772 689 38.9% 482 27.2% 281 15.9% Nov 1,710 671 39.2% 514 30.1% 315 18.4% Dec 1,752 738 42.1% 600 34.2% 365 20.8% Yr Total 20,002 10,051 50.2% 7,985 39.9% 5,179 25.9%

Equal Day 2 Low Temp with Precip Month Total Days Equal Day 1 Rain Equal Day 2 Rain Equal Both Rain Jan 210 69 32.9% 76 36.2% 42 20.0% Feb 206 79 38.3% 75 36.4% 45 21.8% Mar 93 45.1% 97 47.1% 59 28.6% Apr 185 104 56.2% 92 49.7% 66 35.7% May 199 52.3% 123 61.8% 80 40.2% Jun 224 126 56.3% 127 56.7% 84 37.5% Jul 315 162 51.4% 159 50.5% 99 31.4% Aug 280 125 44.6% 122 43.6% 72 25.7% Sep 202 78 38.6% 37.6% 44 Oct 222 60 27.0% 18.9% Nov 218 61 28.0% 64 29.4% 32 14.7% Dec 30.5% 29.0% 30 14.3% Yr Total 2,677 1,125 42.0% 1,132 42.3% 695 26.0%

Positive Day 2 Avg Temp with Precip Month Total Days Positive Day 1 Rain Positive Day 2 Rain Positive Both Rain Jan 1,776 504 28.4% 419 23.6% 212 11.9% Feb 1,620 546 33.7% 396 24.4% 229 14.1% Mar 1,844 650 35.2% 502 27.2% 269 14.6% Apr 1,777 661 37.2% 561 31.6% 295 16.6% May 1,816 796 43.8% 783 43.1% 423 23.3% Jun 1,774 800 45.1% 786 44.3% 457 25.8% Jul 1,719 686 39.9% 677 39.4% 355 20.7% Aug 1,648 602 36.5% 595 36.1% 296 18.0% Sep 1,626 477 29.3% 435 26.8% 204 12.5% Oct 1,685 385 22.8% 308 18.3% 160 9.5% Nov 1,588 389 24.5% 294 18.5% 145 9.1% Dec 1,642 438 26.7% 349 21.3% 185 11.3% Yr Total 20,515 6,934 33.8% 6,105 29.8% 3,230 15.7%

Negative Day 2 Avg Temp with Precip Month Total Days Negative Day 1 Rain Negative Day 2 Rain Negative Both Rain Jan 1,582 636 40.2% 727 46.0% 413 26.1% Feb 1,422 611 43.0% 771 54.2% 428 30.1% Mar 1,517 715 47.1% 868 57.2% 505 33.3% Apr 1,460 728 49.9% 839 57.5% 504 34.5% May 1,497 865 57.8% 898 60.0% 590 39.4% Jun 1,434 810 56.5% 807 56.3% 516 36.0% Jul 1,568 774 49.4% 811 51.7% 451 28.8% Aug 1,634 777 47.6% 761 46.6% 445 27.2% Sep 1,581 631 39.9% 685 43.3% 381 24.1% Oct 1,656 519 31.3% 35.6% 276 16.7% Nov 1,630 545 33.4% 649 39.8% 332 20.4% Dec 1,687 619 36.7% 717 42.5% 367 21.8% Yr Total 18,668 8,230 44.1% 9,123 48.9% 5,208 27.9%

Equal Day 2 Avg Temp with Precip Month Total Days Equal Day 1 Rain Equal Day 2 Rain Equal Both Rain Jan 83 34 41.0% 30 36.1% 20 24.1% Feb 93 39 41.9% 35 37.6% 18 19.4% Mar 80 32 40.0% 28 35.0% 14 17.5% Apr 44 47.3% 43 46.2% 25 26.9% May 128 66 51.6% 60 46.9% 33.6% Jun 122 57 46.7% 48 39.3% 23.0% Jul 154 85 55.2% 67 43.5% 42 27.3% Aug 159 62 39.0% 72 45.3% 24.5% Sep 123 40 32.5% 24.4% 16 13.0% Oct 100 29 29.0% 20.0% 9 9.0% Nov 112 22.3% 19 17.0% 10 8.9% Dec 25.9% 26 23.2% 12.5% Yr Total 1,359 542 39.9% 478 35.2% 278 20.5%

Frontal Passage Cold Front Warm Front Day 2 High within 1 degree of Day 1 Low 573 Frontal Passages Warm Front Day 2 Low within 1 degree of Day 1 High 95 Frontal Passages

Cold Front (Change in Max Temp) Month -40+ -30 to -39 -20 to -29 -10 to -19 0 to -9 Total Tot % January 1 16 20 24 11 72 12.6% February 2 7 15 33 77 13.4% March 19 22 69 12.0% April 4 23 12 55 9.6% May 9 28 4.9% June 5 8 2.6% July 6 1.2% August 1.6% September 3 13 34 5.9% October 10 38 6.6% November 29 27 73 12.7% December 35 37 96 16.8% Year Total 51 139 224 153 573

Warm Front (Change in Max Temp) Month 0 to 9 10 to 19 20 to 29 30 to 39 40+ Total Tot % January 4 7 3 1 15 15.8% February 5 2 11 11.6% March 9 9.5% April 6 6.3% May June 1.1% July August 0.0% September October November 14 14.7% December 12 12.6% Year Total 31 36 22 95

Extreme Daily Changes (Day 2 compared to Day 1) High Temp Change Low Temp Change Ave Temp Change Below -49.5 2 -49.5 to -40 28 -39.5 to -30 213 6 9 -29.5 to -20 139 171 311 -19.5 to -10 5,031 2,524 3,411 -9 .5 to 0 13,244 19,978 17,655 0.5 to 10 15,319 15,080 18,170 10.5 to 20 4,556 2,591 2,243 20.5 to 30 676 181 97 30.5 to 40 68 10 5 Above 40 7 1

Final Thoughts (Fun Facts) High Temperatures Average Daily Change If D2 Warmer → +7.7° (50.9%) If D2 Colder → -8.8° (44.6%) Low Temperatures If D2 Warmer → +6.0° (44.1%) If D2 Colder → -5.4° (49.3%) Average Temperatures If D2 Warmer → +5.2° (50.6%) If D2 Colder → -5.7° (46.6%)

Final Thoughts Day 2 High Warmer than Day 1 Day 2 Low Cooler than Day 1 Precip on Day 1 Day 2 High More Likely to be Warmer Day 2 Low More Likely to be Cooler Precip on Day 2 Day 2 High More Likely to be Cooler Day 2 Low More Likely to be Warmer Many More Cold Fronts than Warm Fronts Fronts Cause ± 10° to 19° Temp Change Most Often

Thank You ???